Currying Debouncing Throttling and Polyfills

Continue your JavaScript Tutorial learning path with hands-on explanation, code practice, and quiz.

Previous Next

Course

JavaScript Tutorial

Estimated Time

8 min

Progress

29%

Track Position

21 / 73

Lesson Overview

Simple Explanation

Currying function ko multiple single-argument functions me convert karta hai. Debouncing rapid events me last call run karta hai. Throttling fixed interval me run limit karta hai. Polyfills old browsers me missing features provide karte hain.

Code Explanation

Neeche custom debounce/throttle helpers aur map polyfill style implementation di gayi hai.

Output Description

Typing event par limited logs aayenge; custom map array transform karega.

Practice Exercise

Array.prototype.filter ka mini polyfill likho aur test cases run karo.

Extra Explanation

Why This Matters

Currying Debouncing Throttling and Polyfills is core to dynamic behavior. Strong fundamentals here help you build forms, API flows, and interactive UI with confidence.

Real-World Workflow

Complex features are usually split into small functions, then verified through focused logging and tiny test cases.

Common Mistakes to Avoid

Avoid uncontrolled globals, weak error handling, and ignored async states. Define clear input-output expectations for each function.

Example + Live Practice

<script>
  const curryAdd = (a) => (b) => a + b;
  console.log(curryAdd(2)(5));

  function debounce(fn, delay) {
    let timer;
    return function (...args) {
      clearTimeout(timer);
      timer = setTimeout(() => fn.apply(this, args), delay);
    };
  }

  function throttle(fn, limit) {
    let inThrottle = false;
    return function (...args) {
      if (inThrottle) return;
      inThrottle = true;
      fn.apply(this, args);
      setTimeout(() => {
        inThrottle = false;
      }, limit);
    };
  }

  if (!Array.prototype.myMap) {
    Array.prototype.myMap = function (cb) {
      const out = [];
      for (let i = 0; i < this.length; i++) {
        out.push(cb(this[i], i, this));
      }
      return out;
    };
  }

  console.log([1, 2, 3].myMap((n) => n * 10));
</script>

Try It Yourself

Loading editor...

Test Your Knowledge

Quiz Coming Soon

Quiz for this lesson is not added yet.

Save Your Work

Lesson ke end par apna code save karein. Dashboard me aap kabhi bhi is saved code ko dobara dekh sakte hain.